[0001] The present invention relates to a magnetic information recorder/reproducer for recording/reproducing
magnetic information on a magnetic medium of the type as defined in the preamble of
claim 1.
[0002] A recorder/reproducer of this type is described in US-A-5,541,685. The known device
includes a holder for supporting therein a shaft which extends through elongated slots
provided in the holder, and elongated slots provided in the legs of a resilient member,
and the shaft further extending through a block which is received in a recess of the
holder. The block is formed with a recess having a resilient pad attached to the bottom
of the recess. The block is biased towards a magnetic head and a magnetic medium until
the resilient member is deformed into the recess and abuts in the operative position
the resilient pad, which would impede further deformation during recording/reproducing
of magnetic information.
[0003] In printing a film having a magnetic recording layer, magnetic information recorded
in the film is read to print the film based on the thus read magnetic information.
[0004] A typical magnetic information reader for reading such magnetic information has a
magnetic head adapted to be brought into contact with film by a leaf spring. The film
is fed kept in contact with the head so that the head can read magnetic information
recorded in the film.
[0005] The head-biasing leaf spring has to be made from a nonmagnetic material because a
leaf spring made from a magnetic material might erase magnetic information, thus making
accurate reading of magnetic information impossible.
[0006] One problem with conventional magnetic information readers is that the leaf spring,
made from a nonmagnetic material, tends to be quickly worn or broken due to contact
with the film to such an extent as to need replacement. Thus, maintenance is a major
problem for conventional magnetic information readers.
[0007] An object of this invention is to provide a magnetic information recorder/reproducer
which requires less maintenance.
[0008] According to this invention as claimed in claim 1, there is provided a magnetic information
recorder/reproducer for recording/reproducing magnetic information on a magnetic medium.
[0009] Other features and objects of the present invention will become apparent from the
following description made with reference to the accompanying drawings, in which:
Fig. 1 is a front view of an embodiment which is not part of this invention;
Fig. 2 is a perspective view of a holder unit of the embodiment of Fig. 1;
Fig. 3 is a front view of another holder unit;
Fig. 4 is a partially cutaway front view of an embodiment of the present invention;
and
Fig. 5 is a perspective view thereof.
[0010] As shown in Fig. 1, a strip of film A having a magnetic recording medium or layer
is fed through a feed path in which is provided a magnetic head 1 for reading magnetic
information recorded in the film A.
[0011] The film A is brought into contact with the magnetic head 1 by a holder unit 2 provided
over the head 1. The holder unit 2 includes a holder 3 formed with a recess 4 having
an opening at the bottom of the holder 3. A pair of protrusions 5 protrude inwardly
from both sides of the opening of the recess 4.
[0012] A resilient member 6 in the form of a metallic leaf spring is mounted in the recess
4. A hard guide layer or member 7 made of a nonmagnetic material is provided on the
side of the resilient member 6 facing the film A.
[0013] The guide layer 7 comprises a resilient sheet strip made of a ceramic material. Here,
zirconia is selected as the ceramic material, and zirconia is formed into a thin sheet
having a thickness of 0.05-0.5 mm.
[0014] In the embodiment, "CERAFLEX A" made by SUMIKIN PHOTON CERAMIX is used as the resilient
sheet strip 7. Such a resilient strip 7 is high in strength, toughness, resilience
and resilient deformability.
[0015] The resilient sheet strip 7 has its both ends inserted in grooves 8 formed in the
side walls of the recess 4 with its central portion deflected outwardly by the resilient
member 6.
[0016] The film A is pressed against the magnetic head 1 by the resilient sheet strip 7
made of a ceramic material and provided on the side of the resilient member 6 facing
the film A. While the head is reading magnetic information recorded in the film A,
the film is fed while kept in contact with the hard resilient sheet strip 7, so that
the resilient member 6 cannot be worn by the film A because it is not in contact with
the film A. The resilient member 6 can be used for a longer time without replacement.
This significantly reduces the labor for maintenance.
[0017] The resilient sheet strip 7 is supported with its both ends inserted in the grooves
8 formed in the holder 3. Thus, if the resilient sheet strip 7 is broken, it can be
easily replaced with a new one.
[0018] In the case of the resilient sheet strip 7 made from zirconia, it is extremely high
in resilient deformability, so that even if the tension of the film A changes widely,
such a change in tension can be absorbed by resilient deformation of the resilient
sheet strip 7. This prevents damage to the resilient sheet strip 7.
[0019] In the embodiment shown in Fig. 1, the guide layer 7 and the resilient member 6 are
separate members. But the guide layer 7 may be formed by thermal-spraying a ceramic
or zirconia on the central part of the resilient member 6 as shown in Fig. 3.
[0020] In the embodiment, film A is shown as a magnetic medium, and magnetic information
recorded in the film is read by the head. But the magnetic medium is not limited to
film but may be e.g. a magnetic tape. Magnetic information is written in such a magnetic
medium.
[0021] An Embodiment of the present invention is now described with reference to Fig. 4
and Fig. 5.
[0022] Below the pair of protrusions 5 there are formed a pair of inwardly downwardly sloping
slits 15 in which are inserted both ends of a resilient member 6 in the shape of a
strip.
[0023] The resilient member 6 is made from a sufficiently resilient ceramic material such
as zirconia. By having its both ends inserted in the slits 15, the resilient member
6 is bent downwardly with its central portion into resilient contact with the magnetic
head 1.
[0024] A block 16 is received in the recess 4. Its downward stroke is limited by abutting
contact of a pair of protrusions 9 provided on both sides thereof with the pair of
protrusions 5.
[0025] The block 16 is biased downward by a biasing means 10 so that its bottom surface
will contact the resilient member 6. In the contact surface with the resilient member
6, the block 16 is formed with a recess 11 that serves to limit resilient deformation
of the resilient member 6.
[0026] The biasing means 10 comprises springs 12 inserted through holes 13 extending through
the holder 3 from its top surface into the recess 4. Their tops bear on adjusting
screws 14 threaded into the holes 13. Thus, by turning the adjusting screws 14, it
is possible to adjust the force of the springs 12 and thus the pressure at which the
resilient member 6 is pressed against the magnetic head 1.
[0027] In use, the magnetic medium A is fed between the magnetic head 1 and the resilient
member 6 while resiliently keeping the magnetic medium A in contact with the magnetic
head 1 by resilience of the resilient member 6 to read and write magnetic information.
[0028] When the tension in the magnetic medium A changes while information is being recorded
or reproduced, the resilient member 6 is deformed resiliently. Since it is resiliently
deformed within the recess 11 formed in the block 16, the member 6 is prevented from
being deformed beyond the limit that can lead to breakage. Thus, the resilient member
6 is less likely to be broken. Moreover, since the resilient member 6 is made from
a ceramic material, it is wear-resistant and less likely to be worn or broken. This
considerably lessens the need of replacements of the resilient member 6. Maintenance
is thus easier.
[0029] Preferably the magnetic medium A is pressed against the magnetic head 1 at a constant
pressure. Since the contact pressure depends on dimensional errors of the holder 3,
it is necessary to adjust the contact pressure before recording or reproducing information.
Specifically, the force of the springs is adjusted to absorb such dimensional errors,
by turning the adjusting screws 14.
[0030] The resilient member is far less likely to be worn because it does not contact the
magnetic medium. Since the resilient member does not directly contact the magnetic
medium, it is possible to use a durable metallic leaf spring made of a magnetic material.
This lightens the maintenance work for replacement of the resilient member due to
wear or breakage.
[0031] Since the guide layer is resilient, the magnetic medium can be always brought into
contact with the magnetic head in an optimum way.
[0032] Further, since the guide layer is a resilient plate strip made of a ceramic material
and having its both ends inserted in grooves formed in both sides of a recess of the
holder, the resilient plate strip can be replaced easily if broken.
[0033] By fixing the ceramic layer to the resilient member, the holder unit can be assembled
easily.
1. A magnetic information recorder/reproducer for recording/reproducing magnetic information
on a magnetic medium (A), comprising a holder (3), a magnetic head (1), a resilient
member (6) supported by said holder(3) for urging the magnetic medium (A) into contact
with said magnetic head (1), said holder (3) being formed with a recess (4), a block
(16) mounted in said recess (4) for urging said resilient member (6) against said
magnetic head (1), and a biasing means (10) for urging said block (16) against said
resilient member (6), said block (16) being formed in surface thereof facing said
resilient member (6) with a recess (11) which allows deformation of said resilient
member (6), characterised in that said resilient member is made of a ceramic material and in that said recess (11) of said block (16) is formed such that during normal operation the
resilient member (6) does not contact the botton of said recess (11); whereas further
deformations of said resilient member (6) within said recess (11) are allowed until
said resilient member (6) contacts the bottom of said recess (11), so as to avoid
breakage of the resilient member.
2. A magnetic information recorder/reproducer as claimed in claim 1, wherein the force
of said biasing means (10) is adjustable.
3. A magnetic information recorder/reproducer as claimed in claim 1 or 2, wherein said
holder (3) is provided with a pair of inwardly downwardly sloping slits (15) for receiving
therein both ends of the strip-shaped resilient member (6).
4. A magnetic information recorder/reproducer as claimed in any one of claims 1 to 3
wherein said ceramic material is zirconia.
5. A magnetic information recorder/reproducer as claimed in any one of claims 1 to 4,
wherein the movement of said block (16) within said recess (4) towards said magnetic
head (1) is limited by an abutting contact of a pair of protrusions (9) provided on
both sides of said block (16), with a pair of protrusions (5) provided on said holder
(3).
1. Magnetische Informationsaufzeichnungs-/Wiedergabeeinrichtung zum Aufzeichnen/Wiedergeben
einer magnetischen Information auf einem magnetischen Medium (A), mit einem Halter
(3), einem Magnetkopf (1), einem federnden Element (6), das durch den Halter (3) gelagert
wird, um das magnetische Medium (A) in Kontakt mit dem Magnetkopf (1) zu drücken,
wobei der Halter (3) mit einer Ausnehmung (4) versehen ist, einem Block (16), der
in der Ausnehmung (4) zum Drücken des federnden Elements (6) gegen den Magnetkopf
(1) montiert ist und einer Belastungseinrichtung (10), um den Block (16) gegen das
federnde Element (6) zu drücken, wobei der Block (16) in seiner dem federnden Element
(6) zugewandten Oberfläche mit einer Vertiefung (11) ausgebildet ist, die eine Verformung
des federnden Elements (6) gestattet, dadurch gekennzeichnet, dass das federnde Element aus einem keramischen Material hergestellt ist, und dass die
Vertiefung (11) des Blocks (16) so ausgebildet ist, dass während eines normalen Betriebs
das federnde Element (6) den Boden der Ausnehmung (11) nicht berührt, während weitere
Verformungen des federnden Elements (6) innerhalb der Ausnehmung (11) gestattet sind,
bis das federnde Element (6) den Boden der Ausnehmung (11) berührt, um dadurch ein
Brechen des federnden Elements zu vermeiden.
2. Magnetische Informationsaufnahme-/Wiedergabeeinrichtung gemäß Anspruch 1 wobei die
Kraft der Belastungseinrichtung (10) einstellbar ist.
3. Magnetische Informationsaufnahme-/Wiedergabeeinrichtung gemäß Anspruch 1 oder 2, wobei
der Halter (3) mit einem Paar nach innen unten abgeschrägter Schlitze (15) zur Aufnahme
beider Enden des streifenförmigen, elastischen Elements (6) versehen ist.
4. Magnetische Informationsaufnahme-/Wiedergabeeinrichtung gemäß einem der Ansprüche
1 bis 3, wobei das keramische Material Zirkonoxid ist.
5. Magnetische Informations-/Wiedergabeeinrichtung gemäß einem der Ansprüche 1 bis 4,
wobei die Bewegung des Blocks (16) innerhalb der Ausnehmung (4) in Richtung auf den
Magnetkopf (1) durch einen Anschlagskontakt eines Paars von Vorsprüngen (9), die an
beiden Seiten des Blocks (16) vorgesehen sind, mit einem Paar von Vorsprüngen (5)
begrenzt ist, die am Halter (3) vorgesehen sind.
1. Un appareil d'enregistrement/reproduction d'informations magnétiques, pour enregistrer/reproduire
de l'information magnétique sur un support magnétique (A), comprenant un support (3),
une tête magnétique (1), un organe élastique (6) supporté par ledit support (3) afin
de mettre le support magnétique (A) en contact avec ladite tête magnétique (1), ledit
support (3) étant formé d'une cavité (4), d'un bloc (16) monté dans ladite cavité
(4) pour placer ledit organe élastique (6) contre ladite tête magnétique, et d'un
organe d'actionnement (10) pour placer ledit bloc (16) contre ledit organe élastique
(6), ledit bloc (16) étant formé sur sa surface en regard dudit organe élastique (6),
avec une cavité (11) permettant une déformation dudit organe élastique (6), caractérisé en ce que ledit organe élastique est réalisé en matériau céramique, et en ce que ladite cavité (11) dudit bloc (16) est formée de manière que, en fonctionnement normal,
l'organe élastique (6) n'entre pas en contact avec le fond de ladite cavité (11) ;
tandis qu'une déformation supplémentaire dudit organe élastique (6) à l'intérieur
de ladite cavité (11) est autorisée, jusqu'à ce que ledit organe élastique (6) entre
en contact avec le fond de ladite cavité (11), de manière à éviter toute rupture de
l'organe élastique.
2. Un appareil d'enregistrement/reproduction d'informations magnétiques selon la revendication
1, dans lequel la force exercée par lesdits moyens d'actionnement (10) est ajustable.
3. Un appareil d'enregistrement/reproduction d'informations magnétiques selon la revendication
1 ou 2, dans lequel ledit support (3) est muni d'une paire de fentes (15), inclinées
intérieurement vers le bas afin de recevoir en leur sein les deux extrémités de l'organe
élastique (6) en forme de bande.
4. Un appareil d'enregistrement/reproduction d'informations magnétiques selon l'une quelconque
des revendications 1 à 3, dans lequel ledit matériau céramique est du zircone.
5. Un appareil d'enregistrement/reproduction d'informations magnétiques selon l'une quelconque
des revendications 1 à 4, dans lequel le déplacement dudit bloc (16) à l'intérieur
de ladite cavité (4) vers ladite tête magnétique (1) est limité par un contact de
butée, produit par une paire de saillies (9), prévues sur les deux côtés dudit bloc
(16), avec une paire de saillies (5) prévues sur ledit support (3).